The order Cetacea includes the whales, dolphins and porpoises and comprise the mammals most fully adapted to aquatic life. It contains 81 known species organized in two suborders: Mysticeti (baleen whales) and Odontoceti (toothed whales, which includes dolphins and porpoises). The order contains several record breaking species, with the Blue Whale being the largest animal known, and the Orca being the most widely distributed animal.
Cetaceans evolved from land mammals that adapted to marine life about 50 million years ago. Over a period of a few millions of years during the Eocene, the cetaceans returned to the sea. Their body is fusiform (spindle-shaped), the forelimbs are modified into flippers, the tiny hindlimbs are vestigial and the tail has horizontal flukes. Cetaceans are nearly hairless, and are insulated by a thick layer of blubber.
Cetaceans inhabit all of the world's oceans, as well as some rivers in South America and Asia. Some species can be found across the globe.
Cetology is the branch of marine science associated with the study of cetaceans.
The Fin Whale (Balaenoptera physalus), also called the Finback Whale, is a mammal which belongs to the baleen whales suborder. It is the second largest whale and also the second largest animal living, after the Blue Whale. The Fin Whale can grow to nearly 27 metres (88 ft) long. It is found in all the world's major oceans, and in waters ranging from the polar to the tropical. It is absent only from waters close to the ice pack at both the north and south poles and relatively small areas of water away from the large oceans. The highest population density occurs in temperate and cool waters. The Fin Whale was heavily hunted during the twentieth century and is listed as an endangered species. The International Whaling Commission (IWC) has issued a moratorium on commercial hunting of this whale.
26 August - Findings from the controversial Japanese whaling research program suggest that a loss of Antarctic sea ice due to increased temperatures has lowered whales' food supply, causing an overall decline in blubber. Read more...
Photo credit: Jaime Ramos, U.S. Antarctic Program, National Science Foundation
Spyhopping is the act of coming out of the water vertically and momentarily staying out of the water in a manner akin to a human treading water. A powerful individual can spyhop as much as half of its body out of the water. The reasons for spyhopping are likely to be similar to those of breaching. Further spyhops may well be used so that the whale can examine its surroundings above the surface — for instance to look at boats. For this a spyhop may be more useful than a breach, because the view is held steady for a longer period of time.